At the present time, drive trains used for electric vehicles are primarily single-speed transmissions, i.e., pure reduction stages having an output speed that is reduced in comparison to an input speed. However, with such a configuration the electric drive must cover the entire rotational speed range, which significantly reduces its overall efficiency. In addition, the realizable speed range is rather narrow.
It has therefore already been proposed to use two-speed transmissions as drive trains for electric vehicles, but up to now these have been configured as conventional manual transmissions with a sliding muff-type coupling. If such a transmission is used, the electric machine can be of smaller design, which results in a clear cost benefit. However, the very configuration of the transmission with a sliding muff-type coupling causes a drop in traction force during shifting. However, for automated drive trains such a drop in traction force means a substantial sacrifice of comfort, which is not acceptable to the customer.